Gottlieb and Shu made the first step to characterize SSPERK\((s,2)\)  methods after they gave the SSPERK\((2,2)\)  method [1]}. Later, Ruuth and Spiteri proved that SSPERK\((s,2)\)  methods have \({\mathcal {C}}=s-1\)  and gave their Shu-Osher representation [2]}. The Butcher form of SSPERK\((s,2)\)  methods is given in Table REF .
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